The invention relates to a plastic hub that its core can be automatically adjusted and, more particularly, to a plastic hub that is placed against its positioning rack, and through the arch-shape surfaces of the arch-shape cylinders formed at the end of the hub blades, an effect of adjusting the position shift is provided so that the shift generated by the revolving of the hub axle can be adjusted by the hub blades as well as the hub core can be automatically adjusted.
Conventionally, an axle is put directly through a central hole in the middle of a fan when the axle is to be fixed into the fan. Because the axle is directly placed in without being aligned, it is liable to generate a position shift when the fan starts to work. Hence, a washer is added to the conventional fan axle to adjust its core. However, because such design needs to use oil-absorbing cotton, the cost of manufacturing will be increased and the process of assembling will become more complicated, which in turn will affect the lifespan of the fan.
Focusing on the above problems, an object of the invention is to utilize the arch-shape cylinders formed at the end of the hub blades, wherein the arch-shape cylinders are placed against their corresponding positioning racks, and through the arch-shape surfaces of the arch-shape cylinders, an effect of adjusting the position shift can be generated.
Another object of the invention is to provide the hub blades that are formed on the outer portion of the plastic hub and distributed like a ring around the hub, wherein the hub blades are placed against the ring-shape concaved slots so that when the axle core is shifted due to assembling, the shift can be adjusted by the hub blades as well as the hub core can be automatically adjusted.
From the above descriptions, the aspects of the inventions can be concluded as follows:
According to the first aspect of the invention, the plastic hub is placed against the positioning rack through the arch-shape cylinders that are located at the ends of the hub blades and have the arch-shape surfaces that provide the position adjusting effect.
According to the second aspect of the invention, the inner portion of the hub main body is a ball construction, which is put into an arch-shape concaved slot, whose shape is in accordance with the shape of the ball construction; the arch-shape concaved slot is located in the middle of the positioning rack to facilitate the hub being put into the positioning rack, and through the arch-shape cylinders located at the end of each hub blades that are distributed like a ring, the position shift generated by the revolving of the hub axle can be adjusted by the hub blades, and the hub core can be automatically adjusted.
According to the third aspect of the invention, because the hub blades are designed titled, the axle can be more supportive in positioning when it is put into the inside of the fan body, making the fan work more smoothly; meanwhile, the position shift generated by the revolving of the hub axle can be adjusted by the hub blades as well as the hub core can be automatically adjusted.
According to the fourth aspect of the invention, because the hub blades are designed titled, the axle has more flexibility when it is put into the inside of the fan body, which means it can absorb the shock and impact generated by the motor rotor to enhance the stability of operation as well as to prolong the lifespan of the fan.
According to the fifth aspect of the invention, because the hub blades are designed titled, the axle has more flexibility in supporting positioning, which means it can absorb the common difference generated by the component processing of the motor rotor and the hub cap so as to achieve easy assembly and to enhance the efficiency of assembly.